How to wish you hadn't forced ipv6 adoption (was "How to force rapid ipv6 adoption")

Mel Beckman mel at
Fri Oct 2 13:35:41 UTC 2015

Every provider gets a /32, according to ARIN.

Type of Resource Request        Criteria to Receive Resource
ISP Initial Allocation
/32 minimum allocation
(/36 upon request)
NRPM 6.5.1<>

  *   Have a previously justified IPv4 ISP allocation from ARIN or one of its predecessor registries, or
  *   Qualify for an IPv4 ISP allocation under current policy, or
  *   Intend to immediately multi-home, or
  *   Provide a reasonable technical justification, including a plan showing projected assignments for one, two, and five year periods, with a minimum of 50 assignments within five years

IPv6 Multiple Discrete Networks
/32 minimum allocation
(/36 upon request)
NRPM 6.11<>

  *   be a single entity and not a consortium of smaller independent entities

-mel via cell

On Oct 2, 2015, at 4:15 AM, Mike Hammett <nanog at<mailto:nanog at>> wrote:

Not all providers are large enough to justify a /32.

Mike Hammett
Intelligent Computing Solutions

Midwest Internet Exchange

----- Original Message -----

From: "Philip Dorr" <tagno25 at<mailto:tagno25 at>>
To: "Rob McEwen" <rob at<mailto:rob at>>
Cc: "nanog group" <nanog at<mailto:nanog at>>
Sent: Thursday, October 1, 2015 11:14:35 PM
Subject: Re: How to wish you hadn't forced ipv6 adoption (was "How to force rapid ipv6 adoption")

On Thu, Oct 1, 2015 at 10:58 PM, Rob McEwen <rob at<mailto:rob at>> wrote:
On 10/1/2015 11:44 PM, Mark Andrews wrote:

IPv6 really isn't much different to IPv4. You use sites /48's
rather than addresses /32's (which are effectively sites). ISP's
still need to justify their address space allocations to RIR's so
their isn't infinite numbers of sites that a spammer can get.

A /48 can be subdivided into 65K subnets. That is 65 *THOUSAND*... not the
256 IPs that one gets with an IPv4 /24 block. So if a somewhat legit hoster
assigns various /64s to DIFFERENT customers of theirs... that is a lot of
collateral damage that would be caused by listing at the /48 level, should
just one customer be a bad-apple spammer, or just one legit customer have a
compromised system one day.

As a provider (ISP or Hosting), you should hand the customers at a
minimum a /56, if not a /48. The provider should have at a minimum a
/32. If the provider is only giving their customers a /64, then they
deserve all the pain they receive.

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